Go to the Ant, Thou Farmer
We humans boast too much. Agribusiness? Ants have it down to a science. “One of the most important developments in human civilisation was the practice of sustainable agriculture,” stated Science Daily. “But we were not the first – ants have been doing it for over 50 million years. Just as farming helped humans become a dominant species, it has also helped leaf-cutter ants become dominant herbivores, and one of the most successful social insects in nature.”
The article discusses how ants have not only perfected the art of growing crops in their nests, but keeping them pest-free. They have symbioses with fungi and bacteria that produce antibiotics, preventing the spread of diseases that would destroy their colonies. Their disposal system is also very elegant. “So how exactly does an ant go about forming partnerships with a fungus and a bacterium?” the article asked. Answer: “No one really knows.”
What they do know, in their own minds, is that evolution explains everything. “Darwin was right about how evolution can affect the whole group” stated another article on Science Daily decorated with a photo of marching ants. They get bad Marx, though, for their opening line:
Worker ants of the world, unite! You have nothing to lose but your fertility. The highly specialized worker castes in ants represent the pinnacle of social organization in the insect world. As in any society, however, ant colonies are filled with internal strife and conflict. So what binds them together? More than 150 years ago, Charles Darwin had an idea and now he’s been proven right.
The punch line is that a scientist at McGill University “discovered how evolution has tinkered with the genes of colonizing insects like ants to keep them from fighting amongst themselves over who gets to reproduce.” Does this idea Dr. Ehab Abouheif called “reproductive constraint” really enhance Darwin’s vitae?
The existence of sterile castes of ants tormented Charles Darwin as he was formulating his Theory of Natural Selection, and he described them as the “one special difficulty, which at first appeared to me insuperable, and actually fatal to my theory.” If adaptive evolution unfolds by differential survival of individuals, how can individuals incapable of passing on their genes possibly evolve and persist?
Darwin proposed that in the case of ant societies natural selection applies not only to the individual, because the individual would never benefit by cutting its own reproduction, but also to the family or group. This study supports Darwin’s prescient ideas, and provides a molecular measure of how an entire colony can be viewed as a single or “superorganism.”
Some prominent evolutionary biologists, however, are not convinced that natural selection can act on groups, as EvoWiki explains (see also 08/26/2004, 05/31/2004, 05/31/2007 and 03/21/2008). In fact, Marek Kohn just wrote a lengthy piece for Nature News about the “unending debate” between evolutionists about whether selection acts on individuals or groups. The rift is deep. “Group-selection thinking is perceived by some as not just an abuse of natural selection but also a denial of it,” on the one hand, but for others, “it is the individualistic perspective that betrays influences from outside science.” For Science Daily to claim that this story “proves” group selection, therefore, seems premature.
The ant farm was fun till Charlie and Tinker Bell showed up (03/16/2006).